Circuit breaker enclosures such as described within U.S. Pat. No. 5,126,918 entitled "Electric Power Distribution Panelboard-Switchboard Assembly" often provide means for venting the enclosures in the event of a serious overcurrent condition within any of the enclosed circuit protection equipment.
Access to the circuit protection equipment within the enclosures is prevented by means of a panel lock to insure that the electrical equipment settings are not changed by unauthorized personnel. One such panel lock is described within U.S. Pat. No. 4,676,081 entitled "Snap-In Semi-Flush Mounted Panel Lock".
The panel locks are generally fabricated from a thermoplastic compound and include plastic means integrally-formed on the lock assembly to retain the locks within the enclosures. The bolts used with such locks are steel fabricated to insure that the locks do not change dimensions over long periods of extended usage.
Upon severe overcurrent conditions whereby several atmospheres of gas pressure are generated within the arc chambers that are incorporated within the circuit protection equipment, gas vents per se may not be sufficient to vent the gas pressure such that the enclosure doors are blown open causing damage to the doors, locks and possible damage to nearby personnel.
One purpose of the invention is to provide a panel lock assembly that is resistant to such high pressures and thereby prevent the doors from becoming blown open without adding substantial cost to the locks or the doors.